Equipment and Methods for Deploying Line in a Wellbore

ABSTRACT

Many wellbore service operations involve placing a line in the wellbore. The line may be used to transmit power to downhole tools, convey signals from downhole-measurement instruments, or both. A problem associated with such operations involves drag forces experienced by the line as process fluids flow through the well, particularly the interior of a tubular body such as casing. The drag forces may cause the line to fail. Magnetizing the line solves this problem. During deployment, the line will migrate and become attached to the casing. Drag forces are significantly reduced because the line is no longer surrounded by moving fluid.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

This disclosure is related in general to wellbore-telemetry technology.In particular, this disclosure relates to improved equipment and methodsfor deploying line in a wellbore.

In recent years, the deployment of fiber lines in subterranean wellboreshas become increasingly frequent. The most common application is toinstall optical fiber as a conduit through which various downholemeasurements may be performed. Such measurements include temperature,pressure, pH, density, resistivity, conductivity, salinity, carbondioxide concentration, asphaltene concentration, etc. Today,optical-fiber technologies may be employed throughout the lifetime of awell—drilling and completion, stimulation, production surveillance andeven after abandonment.

Optical fiber may be deployed in several ways. For example, the fiberline may be preinstalled in equipment and tools and lowered into thewell, it may be pumped downhole such that it unfurls as it follows thefluid down the well, and it may be lowered into the wellbore in the samemanner as a wireline. It is also desirable to perform some of theaforementioned measurements during well cementing operations.

After a well is drilled, the conventional practice in the oil and gasindustry consists of lining the well with a metal casing. An annulararea is thus formed between the casing and the subterranean formation. Acementing operation is then conducted with the goal of filling theannular area with cement slurry. After the cement sets, the combinationof casing and set cement strengthens the wellbore and provides hydraulicisolation between producing zones through which the well penetrates.

A thorough discussion of the primary cementing process may be found inthe following publication: Piot B. and Cuvillier G.: “PrimaryCementing,” in Nelson E. B. and Guillot D. (eds.): Well Cementing—2^(nd)Edition, Houston: Schlumberger (2006): 459-501.

Optical fiber line may be deployed during primary cementing by attachingit to a wiper plug. A number of methods have been described. One methodinvolves a spool of fiber line, with one end of the fiber connected tothe wiper plug. The spool remains at the top of the well, either insideor outside the wellhead. The spool dispenses fiber line as the wiperplug travels through the casing string. A second method attaches thefiber-line spool to the wiper plug, with one end of the fiber attachedto the wellhead. The spool unfurls fiber as the plug travels through thecasing string.

Both methods described above pose difficulties. If the fiber line isfixed at the top of the well, fluids pumped into the well at thewellhead may exert a drag force that can break the fiber. The drag forcemay be exacerbated by the high velocity of fluids falling in vacuuminside the casing due to a U-tubing effect. If the fiber is fixed on thewiper plug and deployed from surface, it may not have sufficient tensilestrength to withstand high plug velocities. These problems are magnifiedas the length of the casing string increases.

Despite the valuable contributions from the art, it would still beadvantageous to be able to deploy fiber lines more reliably.

SUMMARY

The present disclosure reveals improved materials and methods for fiberdeployment.

In an aspect, embodiments relate to systems that convey signals.

In a further aspect, embodiments relate to systems for deploying a linein a subterranean wellbore.

In yet a further aspect, embodiments relate to methods for deployinglines in a subterranean wellbore.

In yet a further aspect, embodiments relate to methods for performingmeasurements in a subterranean well.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of embodiments of the disclosure, wherein amagnetized line is dispensed from two independent apparatuses.

DETAILED DESCRIPTION

The disclosure may pertain to the treatment of vertical wells, but isequally applicable to wells of any orientation. The disclosure maypertain to hydrocarbon production wells, but it is to be understood thatthe disclosure may also be applicable to wells for production of otherfluids, such as water or carbon dioxide or, for example, for geothermalwells, injection, or storage wells. This disclosure may be applicable tooffshore and land wells. It should also be understood that throughoutthis specification, when a concentration or amount range is described asbeing useful, or suitable, or the like, it is intended that any andevery concentration or amount within the range, including the endpoints, is to be considered as having been stated. Furthermore, eachnumerical value should be read once as modified by the term “about”(unless already expressly so modified) and then read again as not to beso modified unless otherwise stated in context. For example, “a range offrom 1 to 10” is to be read as indicating each and every possible numberalong the continuum between about 1 and about 10. In other words, when acertain range is expressed, even if only a few specific data points areexplicitly identified or referred to within the range, or even when nodata points are referred to within the range, it is to be understoodthat the Applicant appreciates and understands that any and all datapoints within the range are to be considered to have been specified, andthat the inventor has possession of the entire range and all pointswithin the range.

Those skilled in the art will appreciate that the term “line” isapplicable to fiber, wire, rope and the like. In addition, a line maycomprise one or more strands of material.

During the course of many well-service operations, process fluids arepumped into the wellbore, recovered from the wellbore, or both. Thewell-service operations include, but are not limited to, drilling,cementing, gravel packing, acidizing and hydraulic fracturing. In thecontext of this disclosure, process fluids include (but are not limitedto) drilling fluids, cement slurries, spacer fluids, chemical washes,completion fluids, acidizing fluids, fracturing fluids, gravel-packfluids and displacement fluids.

Operators frequently install lines in the wellbore before, during andafter well-service operations. The lines may comprise electricalconductors, optical fibers or both. The lines may be used to provideelectrical power to tools installed downhole, convey signals to surfacefrom measurement instruments installed downhole, or both. The tools maydeliver energy in the form of one or more in the list comprising:electricity, heat, acoustic waves, magnetic fields, microwaves, gammarays, x-rays and neutrons. Some instruments may also measure one or morewellbore parameters, including (but not limited to) temperature,pressure, distance, pH, density, resistivity, conductivity, salinity,carbon dioxide concentration and asphaltene concentration. The measuredinformation may be transmitted as signals to surface via one or moreoptical fibers. Such information allows operators to directly monitorthe progress of a well-service operation.

As stated earlier, fibers or lines installed inside a tubular body in asubterranean well are subject to drag forces exerted by fluids flowingthrough the tubular body. Such drag forces can cause fiber or linebreakage, severing the conduit by which the operator provides power todownhole devices, monitors downhole parameters or both. The drag forcesmay be minimized if the fibers or lines become attached to the interiorsurface of the tubular body. Under these circumstances, the drag forceexerted by the fluid will be countered by friction forces between thetubular body and the line.

The Applicant has surprisingly discovered that, during deployment, amagnetized line or fiber will become attached to the interior surface ofa tubular body, provided the tubular body comprises a material thatresponds to a magnetic field. Most tubular bodies installed in asubterranean well are made of carbon steel—a highly magnetic material.The Applicant has also discovered that a magnetizable line or fiber maybe constructed by incorporating magnetizable particles in the protectivejacket surrounding the line or fiber.

Embodiments relate to systems that convey signals. The signals may be inthe form of electrical impulses or light. The system comprises asignal-conveyance medium. The medium is a line comprising one or moreelectrical conductors such as a wire, one or more optical fibers, or acombination of electrical conductors and optical fibers. The electricalconductors and fibers may be in separate strands that operateindependently. The line may further comprise sensors, preferablydistributed along the length of the line, and enabling one to monitorone or more measurement parameters along the length of the tubular body.

The line is surrounded by a protective jacket embedded with magnetizableparticles. The particles preferably comprise one or more ferromagneticmaterials. Suitable ferromagnetic materials include, but are not limitedto, chromium (IV) oxide, cobalt, dysprosium, ferrite, gadolinium,gallium manganese arsenide, iron, magnetite, neodymium-boron, nickel,permalloy, samarium-cobalt, suessite, yttrium iron garnet, orcombinations thereof. Of these, ferrite is most preferred. The particlesize of the ferromagnetic materials is preferably between 5 and 50micrometers, and more preferably between 10 and 20 micrometers. Theferromagnetic-particle concentration in the protective jacket ispreferably between about 5% and 66% by volume, more preferably betweenabout 5% and 50% by volume and most preferably between about 5% and 20%by volume. The thickness of the protective jacket is preferably betweenabout 30 to 75 micrometers, and more preferably between about 40 to 50micrometers.

Means for magnetizing the particles embedded in the protective jacketmay comprise a magnetic coil around which the line is wrapped. When theline is deployed in the subterranean well, it may exhibit a regularsuccession of positive and negative poles.

Embodiments relate to systems for deploying a line in a subterraneanwellbore. The systems comprise a device that travels down the tubularbody inside the wellbore. The device may be, but would not be limitedto, a plug, a dart, a ball, a bomb, a sonde or a canister. The systemsfurther comprise an apparatus for dispensing the line, the linecomprising a signal-conveyance medium surrounded by a protective jacketembedded with magnetizable particles. The line may be dispensed from aspool. The line is preferably continuous and connected to the device.The systems also comprise means for magnetizing the particles.

The medium is a line comprising one or more electrical conductors suchas a wire, one or more optical fibers, or a combination of electricalconductors and optical fibers. The electrical conductors and fibers maybe in separate strands that operate independently.

The line is surrounded by a protective jacket embedded with magnetizableparticles. The particles preferably comprise one or more ferromagneticmaterials. Suitable ferromagnetic materials include, but are not limitedto, chromium (IV) oxide, cobalt, dysprosium, ferrite, gadolinium,gallium manganese arsenide, iron, magnetite, neodymium-boron, nickel,permalloy, samarium-cobalt, suessite, yttrium iron garnet, orcombinations thereof. Of these, ferrite is most preferred. The particlesize of the ferromagnetic materials is preferably between 5 and 50micrometers, and more preferably between 10 and 20 micrometers. Theferromagnetic-particle concentration in the protective jacket ispreferably between about 5% and 66% by volume, more preferably betweenabout 5% and 50% by volume and most preferably between about 5% and 20%by volume. The thickness of the protective jacket is preferably betweenabout 30 to 75 micrometers, and more preferably between about 40 to 50micrometers.

Means for magnetizing the particles embedded in the protective jacketmay comprise a magnetic coil around which the line is wrapped. When theline is deployed in the subterranean well, it will exhibit a regularsuccession of positive and negative poles.

In an embodiment, there are three principal elements. The first elementis the device that travels down a tubular body inside the subterraneanwellbore. In this embodiment, the first element is presented as a wiperplug; however, those skilled in the art will appreciate that otherdevices such as sondes, darts, balls, canisters, bombs and the likewould be equally appropriate. The second element is a first apparatusfor dispensing line, comprising a first reel of line comprising thesignal-conveyance medium. The reel may further comprise the means formagnetizing the particles—it may contain the aforementioned magneticcoil. The line is attached to the wiper plug, and is able to be unwoundfrom the first reel of the first apparatus as the wiper plug travelsthrough the tubular body. The third element is a second apparatus fordispensing line, comprising a second reel of line. The line wound aroundboth the first and second apparatuses is one continuous line. The secondapparatus is installed at a location away from the device; however, linefrom the second reel may also be unwound as the device travels throughthe tubular body. In this way, stress on the line is minimized duringdeployment. Those skilled in the art will recognize that the line maycomprise a bundle of individual strands, each strand having the abilityto operate independently. For example, one or more strands may transmitmeasurement data, while other strands may transmit power to operatetools located downhole.

FIG. 1 is an illustration of embodiments of the present disclosure. Thefirst element, in this case a wiper plug 1, is installed in a tubularbody 2. The second element, a first apparatus 3 for dispensing line, isattached to the wiper plug 1. The magnetizable line 4 is continuousbetween the first device 3 and the third element—the second apparatus 5for dispensing line. In this embodiment, the third element is fixedinside a wellhead 6. As process fluid 7 is pumped into the wellhead, thewiper plug 1 and second element 3 travel through the tubular body 2,away from the third element. Each dispensing device (3 and 5) may deployline 4 simultaneously as the wiper plug 1 travels through the tubularbody; therefore, because the path of least resistance will be followed,stress on the line during deployment is minimized. The magnetized line 4migrates and becomes attached to the tubular body 2.

Alternate embodiments may not feature two line-dispensing apparatuses;instead, one apparatus may be fixed at the surface—outside or inside thewellhead. Or, one apparatus may be fixed on the wiper plug or otherdevice.

Process fluid 7 may comprise (but not be limited to) drilling fluid,cement slurry, spacer fluid, chemical wash, completion fluid, acidizingfluid, fracturing fluid, gravel-pack fluid and displacement fluid.

The wiper plug 1 may contain a chemical substance that may be releasedat some point during its displacement through the tubular body 2.

One or more instruments may be attached to the wiper plug 1, theinstruments measuring one or more parameters in the list comprising:temperature, pressure, distance, pH, density, resistivity, conductivity,salinity, carbon dioxide concentration and asphaltene concentration.

The line 4 may deliver power to tools that emit energy in the form ofone or more types in the list comprising: electricity, heat, acousticwaves, magnetic fields, microwaves, gamma rays, x-rays and neutrons. Theline 4 may also comprise one or more strands, each strand able tooperate independently. The line may further comprise sensors, preferablydistributed along the length of the line, and enabling one to monitorone or more measurement parameters along the tubular body.

Embodiments relate to methods for deploying a line in a subterraneanwellbore. A continuous line is selected, wherein the line comprises asignal-conveyance medium and a protective jacket surrounding theconveyance medium. The conveyance medium comprises at least oneelectrical conductor, or at least one optical fiber, or both. Theelectrical conductors and fibers may be in separate strands that operateindependently. Magnetizable particles are embedded in the protectivejacket. Prior to or during a wellbore-service treatment, the particlesare magnetized, preferably in an alternating and regularpositive-negative-positive configuration.

The line is continuous, and is attached to a device that travels througha tubular body in the wellbore. Both are inserted into the tubular body.A process fluid is pumped into the wellhead, the device is released andbegins to travel through the tubular body. As pumping continues, theline is dispensed into the wellbore and becomes magnetically attached tothe interior surface of the tubular body.

The particles preferably comprise one or more ferromagnetic materials.Suitable ferromagnetic materials include, but are not limited to,chromium (IV) oxide, cobalt, dysprosium, ferrite, gadolinium, galliummanganese arsenide, iron, magnetite, neodymium-boron, nickel, permalloy,samarium-cobalt, suessite, yttrium iron garnet, or combinations thereof.Of these, ferrite is most preferred. The particle size of theferromagnetic materials is preferably between 5 and 50 micrometers, andmore preferably between 10 and 20 micrometers. Theferromagnetic-particle concentration in the protective jacket ispreferably between about 5% and 66% by volume, more preferably betweenabout 5% and 50% by volume and most preferably between about 5% and 20%by volume. The thickness of the protective jacket is preferably betweenabout 30 to 75 micrometers, and more preferably between about 40 to 50micrometers.

Referring to FIG. 1, some embodiments comprise several steps. Acontinuous magnetizable line 4 is selected. The line may comprise one ormore individual strands, each strand having the ability to operateindependently. A portion of the line is wound around a first reel in afirst apparatus 3 for dispensing line. The other portion of the line iswound around a second reel in a second apparatus 5 for dispensing line.The first apparatus 3 is attached to a wiper plug 1 that travels througha tubular body 2, and the combination is inserted into the tubular body2 connected to a wellhead 6. The second apparatus 5 is fixed inside thewellhead 6 such that the first apparatus 3 may travel away in thetubular body 2 when the wiper plug 1 is released. Process fluid 7 ispumped into the wellhead 6, releasing the wiper plug 1 and forcing thewiper plug to begin traveling through the tubular body 2. Continuedpumping of process fluid 7 allows the line 4 to unwind from the firstapparatus 3, the second apparatus 5 or both as the wiper plug 1 travelsthrough the tubular body 2. Prior to or during deployment, the line 4 ismagnetized. Preferably, alternating and regularpositive-negative-positive poles exist along the line 4. Duringdeployment, the line migrates to the surface of the tubular body. Theline-deployment process is complete when the wiper plug 1 lands on floatequipment at the end of the tubular body 2.

Alternate embodiments may not feature two line-dispensing apparatuses;instead, one apparatus may be fixed at the surface—outside or inside thewellhead. Or, one apparatus may be fixed on the wiper plug or otherdevice.

Process fluid 7 may comprise (but not be limited to) drilling fluid,cement slurry, spacer fluid, chemical wash, completion fluid, acidizingfluid, fracturing fluid, gravel-pack fluid and displacement fluid.

The first element 1 may contain a chemical substance that may bereleased at some point during its displacement through the tubular body2.

The first element 1 may contain one or more instruments that measure oneor more parameters in the list comprising: temperature, pressure,distance, pH, density, resistivity, conductivity, salinity, carbondioxide concentration and asphaltene concentration.

The line 4 may supply power to downhole devices that deliver energy inthe form of one or more in the list comprising: electricity, heat,acoustic waves, magnetic fields, microwaves, gamma rays, x-rays andneutrons. The line 4 may comprise one or more strands, each strand ableto operate independently. The line may further comprise sensors,preferably distributed along the length of the line, and enabling one tomonitor one or more measurement parameters along the tubular body.

Embodiments relate to methods for performing measurements in asubterranean wellbore. A continuous line is selected, wherein the linecomprises a signal-conveyance medium and a protective jacket surroundingthe conveyance medium. The conveyance medium comprises at least oneelectrical conductor, or at least one optical fiber, or both. Theelectrical conductors and fibers may be in separate strands that operateindependently. Magnetizable particles are embedded in the protectivejacket. Prior to or during a wellbore-service treatment, the particlesare magnetized, preferably in an alternating and regularpositive-negative-positive configuration. The line may further comprisesensors, preferably distributed along the length of the line, andenabling one to monitor one or more measurement parameters along thetubular body. For example, one may measure the temperature of thetubular body versus depth, and locate the top of the cement column inthe annulus.

The line is continuous, and is attached to a device that travels througha tubular body in the wellbore. Both are inserted into the tubular body.A process fluid is pumped into the wellhead, the device is released andbegins to travel through the tubular body. As pumping continues, theline is dispensed into the wellbore and becomes magnetically attached tothe interior surface of the tubular body.

During deployment or after the device has landed at the bottom of thetubular body, measurements are performed. The measurement parameters mayinclude, but would not be limited to, temperature, pressure, distance,pH, density, resistivity, conductivity, salinity, carbon dioxideconcentration and asphaltene concentration. The measurements are thenconverted to one or more signals that may be transmitted through theline to the surface.

The particles preferably comprise one or more ferromagnetic materials.Suitable ferromagnetic materials include, but are not limited to,chromium (IV) oxide, cobalt, dysprosium, ferrite, gadolinium, galliummanganese arsenide, iron, magnetite, neodymium-boron, nickel, permalloy,samarium-cobalt, suessite, yttrium iron garnet, or combinations thereof.Of these, ferrite is most preferred. The particle size of theferromagnetic materials is preferably between 5 and 50 micrometers, andmore preferably between 10 and 20 micrometers. Theferromagnetic-particle concentration in the protective jacket ispreferably between about 5% and 66% by volume, more preferably betweenabout 5% and 50% by volume and most preferably between about 5% and 20%by volume. The thickness of the protective jacket is preferably betweenabout 30 to 75 micrometers, and more preferably between about 40 to 50micrometers.

Process fluid may comprise (but not be limited to) drilling fluid,cement slurry, spacer fluid, chemical wash, completion fluid, acidizingfluid, fracturing fluid, gravel-pack fluid and displacement fluid.

The device may contain a chemical substance that may be released at somepoint during its displacement through the tubular body.

The line may supply power to downhole tools that deliver energy in theform of one or more in the list comprising: electricity, heat, acousticwaves, magnetic fields, microwaves, gamma rays, x-rays and neutrons.

The line may comprise one or more strands, each strand able to operateindependently.

The preceding description has been presented with reference to presentlypreferred embodiments of the disclosure. Persons skilled in the art andtechnology to which this disclosure pertains will appreciate thatalterations and changes in the described structures and methods ofoperation can be practiced without meaningfully departing from theprinciple, and scope of this disclosure. Accordingly, the foregoingdescription should not be read as pertaining only to the precisestructures described and shown in the accompanying drawings, but rathershould be read as consistent with and as support for the followingclaims, which are to have their fullest and fairest scope.

1. A system for deploying a line in a subterranean wellbore, comprising:(i) a tubular body; (ii) a device that travels through the interior ofthe tubular body; (iii) a first apparatus for dispensing line,comprising a first reel of line; (iv) a second apparatus for dispensingline, comprising a second reel of line, wherein the line wound aroundboth the first and second apparatuses is one continuous line, the linebeing a signal-conveyance medium comprising at least one electricalconductor or at least one optical fiber, or both; (v) a protectivejacket surrounding the line, comprising magnetizable particles; and (vi)means for magnetizing the particles.
 2. The system of claim 1, whereinthe magnetizable particles are ferromagnetic.
 3. The system of claim 1,wherein the magnetizable particles comprise chromium (IV) oxide, cobalt,dysprosium, ferrite, gadolinium, gallium manganese arsenide, iron,magnetite, neodymium-boron, nickel, permalloy, samarium-cobalt,suessite, yttrium iron garnet, or combinations thereof.
 4. The system ofclaim 1, wherein the magnetizable-particle concentration in theprotective jacket is between about 5% and about 66% by volume.
 5. Thesystem of claim 1, wherein the thickness of the protective layer isbetween about 30 and about 75 micrometers.
 6. The system of claim 1,further comprising sensors distributed along the length of the line. 7.A method for deploying a line in a subterranean well, comprising: (i)selecting a continuous line, wherein the line comprises: (a) asignal-conveyance medium comprising at least one electrical conductor orat least one optical fiber, or both; and (b) a protective jacketsurrounding the conveyance medium, comprising magnetizable particles;(ii) magnetizing the particles in the protective layer; (iii) attachingthe line to a device that travels through a tubular body in thewellbore, and inserting both inside the tubular body; (iv) pumping aprocess fluid into the wellhead, releasing the device, and allowing thedevice to begin traveling through the tubular body; and (v) continuingto pump process fluid, allowing the line to extend and becomemagnetically attached to the tubular body as the device travels throughthe tubular body.
 8. The method of claim 7, wherein the magnetizableparticles are ferromagnetic.
 9. The method of claim 7, wherein themagnetizable particles comprise chromium (IV) oxide, cobalt, dysprosium,ferrite, gadolinium, gallium manganese arsenide, iron, magnetite,neodymium-boron, nickel, permalloy, samarium-cobalt, suessite, yttriumiron garnet, or combinations thereof.
 10. The method of claim 7 whereinthe magnetizable-particle concentration in the protective jacket isbetween about 5% and about 66% by volume.
 11. The method of claim 7,wherein the thickness of the protective layer is between about 30 andabout 75 micrometers.
 12. The method of claim 7, wherein the device is aplug, dart, ball, bomb, sonde or canister.
 13. The method of claim 7,wherein the line comprises one or more strands, each strand able tooperate independently.
 14. The method of claim 7, wherein the devicecontains one or more instruments that measure one or more parameters inthe group consisting of temperature, pressure, distance, pH, density,resistivity, conductivity, salinity, carbon dioxide concentration andasphaltene concentration.
 15. The method of claim 7, wherein the linedelivers power to tools that emit energy in the form of one or moretypes in the group consisting of electricity, heat, acoustic waves,magnetic fields, microwaves, gamma rays, x-rays and neutrons.
 16. Amethod for performing measurements in a subterranean well, comprising:(i) selecting a continuous line, wherein the line comprises: (a) asignal-conveyance medium comprising at least one electrical conductor orat least one optical fiber, or both; and (b) a protective jacketsurrounding the conveyance medium, comprising magnetizable particles;(ii) magnetizing the particles in the protective layer; (iii) attachingthe line to a device that travels through a tubular body in thewellbore, and inserting both inside the tubular body; (iv) pumping aprocess fluid into the wellhead, releasing the device, and allowing thedevice to begin traveling through the tubular body; (v) continuing topump process fluid, allowing the line to extend and become magneticallyattached to the tubular body as the device travels through the tubularbody; (vi) measuring one or more parameters selected from the groupconsisting of temperature, pressure, distance, pH, density, resistivity,conductivity, salinity, carbon dioxide concentration and asphalteneconcentration; and (vii) transmitting the measurements through the line.17. The method of claim 16, wherein the magnetizable particles areferromagnetic.
 18. The method of claim 16, wherein the device is a plug,dart, ball, bomb, sonde or canister.
 19. The method of claim 16, whereinthe device contains one or more instruments that measure one or moreparameters in the group consisting of temperature, pressure, distance,pH, density, resistivity, conductivity, salinity, carbon dioxideconcentration and asphaltene concentration.
 20. The method of claim 16,wherein the line delivers power to tools that emit energy in the form ofone or more types in the group consisting of electricity, heat, acousticwaves, magnetic fields, microwaves, gamma rays, x-rays and neutrons.